Tag Archives: egg mortality

I have got to that stage in my career where retirement is no longer a distant speck on the horizon; something that 20 years ago I never even thought about, but which now I am actually looking forward to reaching. Don’t get me wrong, I have, in the main, enjoyed what I have been paid to do for the last 40 years, but I’m looking forward to a change of pace and a change of priorities. I’m not planning on leaving entomology and ecology, or putting my collecting equipment in a cupboard, throwing my field guides away and burning all my reprints in a huge bonfire. Nor do I plan on deleting my EndNote™ files and database when I retire to our house in Languedoc-Roussillon to sit next to the pool with a never-emptying glass of red wine and gently pickle myself in the sun*. I’m just looking forward to approaching it in a different way; my plan is to stop initiating the writing scientific papers, but instead to expand on the outreach, to blog more and to write books for a wider audience. I want to spread the joys and wonders of entomology to the world, and hopefully, supplement my pension a bit to make sure that I can keep that glass filled with red wine and heat the swimming pool in the winter 🙂

I’m planning a gradual retirement, a slow(ish) canter towards the day (September 30th 2020) when I finally vacate my university office and move full-time into my converted attic in the Villa Lucie surrounded by my books and filing cabinets with a superb view of the mountains.

The view from my study to be – I will have to stand up to see it, but exercise is good for you 🙂

I have already reached a number of milestones, I took on my last ever PhD student (as Director of Studies) this month (June 7th) and submitted my final grant application as a PI (June 10th).

I must admit that it is a bit of funny feeling, but a remarkably rewarding one in many ways. I look at my former colleagues who have already retired productively and enjoyably, and I’m envious, so I know that I am making the right decision despite the slight feeling of apprehension. I now have a dilemma. As Jeff Ollerton points out, when you have been around a while, in my case it is almost 40 years since I started my PhD**, you build up a substantial amount of data, especially, if as I have, you have supervised over 150 undergraduate research projects, an equal number of MSc research projects and over 50 PhD students. Much of these data are fragmentary, not significant or even lost (sadly when I moved from Imperial College, they threw away the hard copies of my undergraduate projects, although I can remember what some of the lost data were about). My ten year sycamore and bird cherry aphid field study from my time in Scotland (1982-1992) remains largely unpublished and my huge twenty year sycamore herbivores data set from Silwood Park (1992-2012) is in the same boat, although parts of the data are ‘out on loan’ to former students of mine and I hope will be analysed and published before I retire.

This leaves however, the data, some of it substantial, which I would like to see the light of day, e.g. a whole set of rabbit behaviour data that I collected one summer with the help of an undergraduate and MSc student, which surprisingly revealed novel insights. Other data, perhaps not as novel, may be of interest to some people and there is a whole bunch of negative and non-significant data, which as Terry McGlynn highlights over on Small Pond Science, does not necessarily mean that it is of no use. I have, as an example of fragmentary, not entirely earth-shattering data, the following to offer. Whilst monitoring aphid egg populations on bird cherry and sycamore trees, in Scotland between 1982 and 1992, I occasionally sampled overwintering eggs of Euceraphis betulae, on some nearby birch (Betula pendula) trees and of Tuberculoides annulatus, on an oak tree (Quercus robur) in my back garden in Peebles.

As far as I know there are no published data on the overwintering egg mortality of these two aphids. Although novel for these two aphid species, the observation of the way the egg populations behave over the winter and the factors causing the mortality have already been described by me for another aphid species (Leather, 1980, 1981). I am therefore unlikely to get them published in any mainstream journal, although I am sure that one of the many predatory journals out here would leap at the chance to take my money and publish the data in the Journal of Non-Peer-Reviewed Entomology 🙂 I could of course publish the data in one of the many ‘amateur’ type, but nevertheless peer-reviewed journals, such as Entomologist’s Monthly Magazine, The Entomologist’s Record, The Entomologist’s Gazette or the British Journal of Entomology & Natural History, which all have long and distinguished histories, three of which I have published in at least once (Leather & Brotherton 1987, Leather, 1989, 2015), but which have the disadvantage of not being published with on-line versions except for those few issues that have been scanned into that great resource, The Biodiversity Heritage Library, so would remain largely inaccessible for future reference.

I thus offer to the world these data collected from four Betula pendula trees in Roslin Glen Nature Reserve in Scotland between 1982 and 1986. On each sampling occasion, beginning at the end of October, 200 buds were haphazardly selected and the number of eggs present in the bud axils recorded. Sampling continued until egg hatch began in the spring.

Figure 1. Mean number of eggs per 100 buds of the aphid Euceraphis betulae present on four Betula pendula trees at Roslin Glen Nature Reserve Scotland***.

The number of eggs laid on the trees varied significantly between years (F = 20.3, d.f. = 4/15, P <0.001) ranging from 12.75 eggs/100 buds in 1983-84 to 683 eggs/100 buds in 1986-87. Mortality occurred at a regular rate over the winter and ranged from between 60% in 1985-86 to 83 % in 1984-85, averaging out at 74% over the five-year study.

So in conclusion, no startling new insights, but just some additional data about aphid egg mortality to add to the somewhat sparse records to date (Leather, 1992). Perhaps it is time for me to write another review 🙂

I write about politics, nature + the environment. Some posts are serious, some not. These are my views, I don't do any promotional stuff and these views are not being expressed for anyone who employs me.

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